Which are necessary

Real wisdom is not the knowledge of everything, but the knowledge of which things in life are necessary, which are less necessary, and which are completely unnecessary to know. Among the most necessary knowledge is the knowledge of how to live well, that is, how to produce the least possible evil and the greatest goodness in one’s life. At present, people study useless sciences, but forget to study this, the most important knowledge.

~ Leo Tolstoy

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